Automatic transmission for vehicle

ABSTRACT

A planetary gear train may include first planetary gear set including first to third rotation elements, second planetary gear set including fourth to sixth rotation elements, third planetary gear set including seventh to ninth rotation elements, fourth planetary gear set including tenth to twelfth rotation elements, fifth planetary gear set including thirteenth to fifteenth rotation elements, first shaft fixed to the first and sixth rotation elements, and input shaft, second shaft fixed to the fourteenth rotation element and output shaft, third shaft fixed to the third and seventh rotation elements, fourth shaft fixed to the fifth and eighth rotation elements, fifth shaft fixed to the ninth and tenth rotation elements, sixth shaft fixed to the eleventh and fifteenth rotation elements, and shafts formed by remaining rotation elements among the first to fifteenth rotation elements not connected to the first to sixth shafts, and each thereof selectively connectable to transmission housing.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.10-2017-0182965 filed on Dec. 28, 2017, the entire contents of which isincorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an automatic transmission for avehicle. More particularly, the present invention relates to a planetarygear train of an automatic transmission for a vehicle that improvespower delivery performance and fuel economy by achieving ten forwardspeeds and widening speed ratio span (or gear ratio span), and secureslinearity of step ratios.

Description of Related Art

Generally, an automatic transmission achieving more speed stages hasbeen developed to enhancing fuel economy and optimizing drivability.

Such an automatic transmission achieving more speed stages is necessaryto maximize power performance and driving efficiency according todownsizing of an engine. Particularly, it is desperately demanded todevelop high efficiency multiple-speeds transmissions having excellentlinearity of step ratios that may be used as an index closely related todrivability including acceleration before and after shift and rhythmicalengine speed to secure competitiveness of automatic transmission field.

However, in the automatic transmission, as the number of speed stagesincrease, the number of internal components increase, and as a result,mountability, cost, weight, transmission efficiency, and the like maystill deteriorate.

Accordingly, development of a planetary gear train which may achievemaximum efficiency with a small number of components may be important toincrease fuel efficiency enhancement effect through the multiple-speeds.

In this background, an eight-speed automatic transmission has beenintroduced recently and a planetary gear train for an automatictransmission facilitating more speed stages is under investigation.

However, since a conventional eight-speed automatic transmission hasgear ratio span of 6.5-7.5 (gear ratio span is an important factor forsecuring linearity of step ratios), improvement of power performance andfuel economy may not be great.

In addition, even though an eight-speed automatic transmission has gearratio span greater than 9.0, it is hard to secure linearity of stepratios. Therefore, driving efficiency of an engine and drivability of avehicle may deteriorate, and thus, development of high efficiencyautomatic transmissions which achieve at least nine forward speeds isnecessary.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and may not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art already known to aperson skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing aplanetary gear train of an automatic transmission for a vehicle havingadvantages of improving power delivery performance and fuel economy byachieving ten forward speeds and one reverse speed and reducing dragloss of clutches and brakes using five planetary gear sets but sixengaging elements.

Various aspects of the present invention are directed to providing aplanetary gear train of an automatic transmission for a vehicle havingfurther advantages of improving torque delivery efficiency anddurability by applying torque parallel way to a planetary gear set at anoutput side and minimizing torque share of each planetary gear set andeach engaging element.

Various aspects of the present invention are directed to providing ahigh-efficiency planetary gear train of an automatic transmission for avehicle having further advantages of increasing flexibility of outputgear ratios and improving linearity of step ratios by use of fiveplanetary gear sets for achieving ten forward speeds and one reversespeed.

A planetary gear train of an automatic transmission for a vehicleaccording to an exemplary embodiment of the present invention mayinclude: an input shaft receiving torque of an engine; an output shaftoutputting torque; a first planetary gear set including first, second,and third rotation elements; a second planetary gear set includingfourth, fifth, and sixth rotation elements; a third planetary gear setincluding seventh, eighth, and ninth rotation elements; a fourthplanetary gear set including tenth, eleventh, and twelfth rotationelements; a fifth planetary gear set including thirteenth, fourteenth,and fifteenth rotation elements; a first shaft fixedly connected to thefirst rotation element and the sixth rotation element and fixedlyconnected to the input shaft; a second shaft fixedly connected to thefourteenth rotation element and the output shaft; a third shaft fixedlyconnected to the third rotation element and the seventh rotationelement; a fourth shaft fixedly connected to the fifth rotation elementand the eighth rotation element; a fifth shaft fixedly connected to theninth rotation element and the tenth rotation element; a sixth shaftfixedly connected to the eleventh rotation element and the fifteenthrotation element; and a plurality of shafts formed by combinations ofremaining rotation elements among the first to fifteenth rotationelements that are not connected to the first shaft to the sixth shaft,and each of them selectively connectable to a transmission housing.

The plurality of shafts may include: a seventh shaft fixedly connectedto the second rotation element and the fourth rotation element andselectively connectable to the transmission housing; an eighth shaftfixedly connected to the twelfth rotation element and selectivelyconnectable to the transmission housing; and a ninth shaft fixedlyconnected to the thirteenth rotation element and selectively connectableto the transmission housing, wherein the second shaft is selectivelyconnectable to the fifth shaft, the third shaft is selectivelyconnectable to the sixth shaft, and the fourth shaft is selectivelyconnectable to the sixth shaft.

The planetary gear train may further include: three clutches, eachselectively connecting any one shaft to another shaft; and three brakes,each selectively connecting any one of the seventh shaft, the eighthshaft, and the ninth shaft to the transmission housing.

The three clutches may include: a first clutch disposed between thesecond shaft and the fifth shaft; a second clutch disposed between thethird shaft and the sixth shaft; and a third clutch disposed between thefourth shaft and the sixth shaft.

The three brakes may include: a first brake disposed between the seventhshaft and the transmission housing; a second brake disposed between theeighth shaft and the transmission housing; and a third brake disposedbetween the ninth shaft and the transmission housing.

The first rotation element may be a first sun gear, the second rotationelement may be a first planet carrier, and the third rotation elementmay be a first ring gear. The fourth rotation element may be a secondsun gear, the fifth rotation element may be a second planet carrier, andthe sixth rotation element may be a second ring gear. The seventhrotation element may be a third sun gear, the eighth rotation elementmay be a third planet carrier, and the ninth rotation element may be athird ring gear. The tenth rotation element may be a fourth sun gear,the eleventh rotation element may be a fourth planet carrier, and thetwelfth rotation element may be a fourth ring gear. The thirteenthrotation element may be a fifth sun gear, the fourteenth rotationelement may be a fifth planet carrier, and the fifteenth rotationelement may be a fifth ring gear.

In one aspect, the first, second, third, fourth, and fifth planetarygear sets may be disposed in a sequence of the first, third, second,fourth, and fifth planetary gear sets from an engine side on an axis ofthe input shaft.

In another aspect, the first, second, third, fourth, and fifth planetarygear sets may be disposed in a sequence of the first, second, third,fourth, and fifth planetary gear sets from an engine side on an axis ofthe input shaft.

A planetary gear train of an automatic transmission for a vehicleaccording to another exemplary embodiment of the present invention mayinclude: an input shaft receiving torque of an engine; an output shaftoutputting torque; a first planetary gear set including first, second,and third rotation elements; a second planetary gear set includingfourth, fifth, and sixth rotation elements; a third planetary gear setincluding seventh, eighth, and ninth rotation elements; a fourthplanetary gear set including tenth, eleventh, and twelfth rotationelements; and a fifth planetary gear set including thirteenth,fourteenth, and fifteenth rotation elements, wherein the first rotationelement is fixedly connected to the input shaft, the fourteenth rotationelement is fixedly connected to the output shaft, the first rotationelement is fixedly connected to the sixth rotation element, the secondrotation element is fixedly connected to the fourth rotation element andselectively connectable to a transmission housing, the third rotationelement is fixedly connected to the seventh rotation element, the fifthrotation element is fixedly connected to the eighth rotation element,the ninth rotation element is fixedly connected to the tenth rotationelement and selectively connectable to the fourteenth rotation element,the eleventh rotation element is fixedly connected to the fifteenthrotation element and selectively connectable to the third rotationelement and the eighth rotation element, the twelfth rotation element isselectively connectable to the transmission housing, and the thirteenthrotation element is selectively connectable to the transmission housing.

The planetary gear train may further include: three clutches, eachselectively connecting any one rotation element to another rotationelement; and three brakes, each selectively connecting any one of thesecond rotation element, the twelfth rotation element, and thethirteenth rotation element to the transmission housing.

The three clutches may include: a first clutch disposed between thetenth rotation element and the fourteenth rotation element; a secondclutch disposed between the third rotation element and the eleventhrotation element; and a third clutch disposed between the eighthrotation element and the eleventh rotation element.

The three brakes may include: a first brake disposed between the secondrotation element and the transmission housing; a second brake disposedbetween the twelfth rotation element and the transmission housing; and athird brake disposed between the thirteenth rotation element and thetransmission housing.

The first rotation element may be a first sun gear, the second rotationelement may be a first planet carrier, and the third rotation elementmay be a first ring gear. The fourth rotation element may be a secondsun gear, the fifth rotation element may be a second planet carrier, andthe sixth rotation element may be a second ring gear. The seventhrotation element may be a third sun gear, the eighth rotation elementmay be a third planet carrier, and the ninth rotation element may be athird ring gear. The tenth rotation element may be a fourth sun gear,the eleventh rotation element may be a fourth planet carrier, and thetwelfth rotation element may be a fourth ring gear. The thirteenthrotation element may be a fifth sun gear, the fourteenth rotationelement may be a fifth planet carrier, and the fifteenth rotationelement may be a fifth ring gear.

In one aspect, the first, second, third, fourth, and fifth planetarygear sets may be disposed in a sequence of the first, third, second,fourth, and fifth planetary gear sets from an engine side on an axis ofthe input shaft.

In another aspect, the first, second, third, fourth, and fifth planetarygear sets may be disposed in a sequence of the first, second, third,fourth, and fifth planetary gear sets from an engine side on an axis ofthe input shaft.

According to exemplary embodiments of the present invention, ten forwardspeeds and one reverse speed may be achieved by combining five planetarygear sets being simple planetary gear sets with six engaging elements.

In addition, since gear ratio span greater than 8.4 is secured, drivingefficiency of the engine may be maximized. In addition, since linearityof step ratios may be secured due to multiple speed stages, drivabilityincluding acceleration before and after shift, rhythmical engine speed,and the like may be improved.

In addition, since ten forward speeds and one reverse speed are achievedby use of five planetary gear sets but the number of engaging elementsis minimized, drag loss of clutches and brakes may be reduced and powerdelivery efficiency and fuel economy may be improved.

In addition, since torque parallel way is applied to a planetary gearset at an output side and torque is evenly shared to each planetary gearset and each engaging element, torque delivery efficiency and durabilitymay be improved.

In addition, since five planetary gear sets are used to achieve tenforward speeds and one reverse speed, flexibility of output gear ratiosmay be increased and linearity of step ratios may be improved.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description, which together serve to explaincertain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a planetary gear train according tovarious exemplary embodiments of the present invention.

FIG. 2 is an operation chart of engaging elements at each speed stage inthe planetary gear train according to the various exemplary embodimentsof the present invention.

FIG. 3 is a schematic diagram of a planetary gear train according tovarious exemplary embodiments of the present invention.

It may be understood that the appended drawings are not necessarily toscale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particularly intendedapplication and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that the present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

Hereinafter, various exemplary embodiments of the present invention willbe described in detail with reference to the accompanying drawings.

However, parts which are not related with the description are omittedfor clearly describing the exemplary embodiments of the presentinvention and like reference numerals refer to like or similar elementsthroughout the specification.

In the following description, dividing names of components into first,second, and the like is to divide the names because the names of thecomponents are the same as each other and an order thereof is notparticularly limited.

FIG. 1 is a schematic diagram of a planetary gear train according tovarious exemplary embodiments of the present invention.

Referring to FIG. 1, a planetary gear train according to variousexemplary embodiments of the present invention includes first, second,third, fourth, and fifth planetary gear sets PG1, PG2, PG3, PG4, and PG5disposed on the same axis, an input shaft IS, an output shaft OS, nineshafts TM1 to TM9 connected to at least one rotation element of thefirst, second, third, fourth, and fifth planetary gear sets PG1, PG2,PG3, PG4, and PG5, engaging elements including three clutches C1 to C3and three brakes B1 to B3, and a transmission housing H.

Torque input from an engine to the input shaft IS is changed bycooperation of the first, second, third, fourth, and fifth planetarygear sets PG1, PG2, PG3, PG4, and PG5, and the changed torque is outputthrough the output shaft OS.

According to the various exemplary embodiments of the present invention,the planetary gear sets are disposed in a sequence of the first, third,fourth, second, and fifth planetary gear sets PG1, PG3, PG4, PG2, andPG5 from an engine side on an axis of the input shaft IS.

The input shaft IS is an input member and torque from a crankshaft ofthe engine is torque-converted through a torque converter to be inputinto the input shaft IS.

The output shaft OS is an output element, is disposed on the same axiswith the input shaft IS, and transmits driving torque to a driving wheelthrough a differential apparatus.

The first planetary gear set PG1 is a single pinion planetary gear setand includes a first sun gear S1 as a first rotation element N1, a firstplanet carrier PC1 as a second rotation element N2 that rotatablysupports a plurality of first pinion gears P1 disposed evenly at anexternal circumference of the first sun gear S1 and engaged with thefirst sun gear S1, and a first ring gear R1 as a third rotation elementN3 that is engaged with the first pinion gears P1 at a radial outer ofthe plurality of first pinion gears P1 to be operably connected to thefirst sun gear S1.

The second planetary gear set PG2 is a single pinion planetary gear setand includes a second sun gear S2 as a fourth rotation element N4, asecond planet carrier PC2 as a fifth rotation element N5 that rotatablysupports a plurality of second pinion gears P2 disposed evenly at anexternal circumference of the second sun gear S2 and engaged with thesecond sun gear S2, and a second ring gear R2 as a sixth rotationelement N6 that is engaged with the second pinion gears P2 at a radialouter of the plurality of second pinion gears P2 to be operablyconnected to the second sun gear S2.

The third planetary gear set PG3 is a single pinion planetary gear setand includes a third sun gear S3 as a seventh rotation element N7, athird planet carrier PC3 as an eighth rotation element N8 that rotatablysupports a plurality of third pinion gears P3 disposed evenly at anexternal circumference of the third sun gear S3 and engaged with thethird sun gear S3, and a third ring gear R3 as a ninth rotation elementN9 that is engaged with the third pinion gears P3 at a radial outer ofthe plurality of third pinion gears P3 to be operably connected to thethird sun gear S3.

The fourth planetary gear set PG4 is a single pinion planetary gear setand includes a fourth sun gear S4 as a tenth rotation element N10, afourth planet carrier PC4 as an eleventh rotation element N11 thatrotatably supports a plurality of fourth pinion gears P4 disposed evenlyat an external circumference of the fourth sun gear S4 and engaged withthe fourth sun gear S4, and a fourth ring gear R4 as a twelfth rotationelement N12 that is engaged with the fourth pinion gears P4 at a radialouter of the plurality of fourth pinion gears P4 to be operablyconnected to the fourth sun gear S4.

The fifth planetary gear set PG5 is a single pinion planetary gear setand includes a fifth sun gear S5 as a thirteenth rotation element N13, afifth planet carrier PC5 as a fourteenth rotation element N14 thatrotatably supports a plurality of fifth pinion gears P5 disposed evenlyat an external circumference of the fifth sun gear S5 and engaged withthe fifth sun gear S5, and a fifth ring gear R5 as a fifteenth rotationelement N15 that is engaged with the fifth pinion gears P5 at a radialouter of the plurality of fifth pinion gears P5 to be operably connectedto the fifth sun gear S5.

Here, the term “operably connected” or the like means at least twomembers are directly or indirectly connected to each other. However, twomembers that are operably connected to each other do not always rotatewith the same rotation speed and in the same rotation direction thereof.

Here, the first rotation element N1 is fixedly connected to the sixthrotation element N6, the second rotation element N2 is fixedly connectedto the fourth rotation element N4, the third rotation element N3 isfixedly connected to the seventh rotation element N7, the fifth rotationelement N5 is fixedly connected to the eighth rotation element N8, theninth rotation element N9 is fixedly connected to the tenth rotationelement N10, and the eleventh rotation element N11 is fixedly connectedto the fifteenth rotation element N15 such that the first, second,third, fourth, and fifth planetary gear sets PG1, PG2, PG3, PG4, and PG5include nine shafts TM1 to TM9.

Here, the term “fixedly connected” or the like means at least twomembers are connected to each other to always rotate without rotationspeed difference. That is, at least two members that are fixedlyconnected to each other always rotate with the same rotation speed andin the same rotation direction thereof. Therefore, it is to beunderstood by a person of an ordinary skill in the art that the term“fixedly connected” or the like differs from the term “operablyconnected” or the like.

The nine shafts TM1 to TM9 will be described in further detail.

The first shaft TM1 is fixedly connected to the first rotation elementN1 (first sun gear S1) and the sixth rotation element N6 (second ringgear R2) and fixedly connected to the input shaft IS to be continuouslyoperated as an input element.

The second shaft TM2 is fixedly connected to the fourteenth rotationelement N14 (fifth planet carrier PC5) and fixedly connected to theoutput shaft OS to be continuously operated as an output element.

The third shaft TM3 is fixedly connected to the third rotation elementN3 (first ring gear R1) and the seventh rotation element N7 (third sungear S3).

The fourth shaft TM4 is fixedly connected to the fifth rotation elementN5 (second planet carrier PC2) and the eighth rotation element N8 (thirdplanet carrier PC3).

The fifth shaft TM5 is fixedly connected to the ninth rotation elementN9 (third ring gear R3) and the tenth rotation element N10 (fourth sungear S4).

The sixth shaft TM6 is fixedly connected to the eleventh rotationelement N11 (fourth planet carrier PC4) and the fifteenth rotationelement N15 (fifth ring gear R5).

The seventh shaft TM7 is fixedly connected to the second rotationelement N2 (first planet carrier PC1) and the fourth rotation element N4(second sun gear S2).

The eighth shaft TM8 is fixedly connected to the twelfth rotationelement N12 (fourth ring gear R4).

The ninth shaft TM9 is fixedly connected to the thirteenth rotationelement N13 (fifth sun gear S5).

The nine shafts TM1 to TM9 fixedly connects a plurality of rotationelements among the rotation elements of the planetary gear sets PG1,PG2, PG3, PG4, and PG5 with each other, are rotation members that areconnected to any one rotation element and rotate with the any onerotation element to transmit torque, are rotation members thatselectively connect any one rotation element with the transmissionhousing H, or are fixed members that directly connect any one rotationelement to the transmission housing H.

Here, the term “selectively connectable” or the like means that aplurality of shafts including the input shaft and the output shaft areconnectable to each other through at least one of the engaging elementsto rotate with the same rotation speed and in the same rotationdirection, or are connectable to the transmission housing through atleast one of the engaging elements to be fixed to the transmissionhousing.

In other words, in a case that the engaging element selectively connectsa plurality of shafts to each other, the plurality of shafts rotate withthe same rotation speed and in the same rotation direction when theengaging element operates but the plurality of shafts are disconnectedfrom each other when the engaging element is released.

In addition, in a case that the engaging element selectively connectsany one shaft to the transmission housing, the corresponding shaft isfixedly connected to the transmission housing when the engaging elementoperates but the corresponding shaft is rotatable when the engagingelement is released.

Therefore, it is to be understood by a person of an ordinary skill inthe art that the term “selectively connectable” or the like differs fromthe term “operably connected” or the like.

Here, the second shaft TM2 is selectively connectable to the fifth shaftTM5, and the third shaft TM3 and the fourth shaft TM4 are selectivelyconnectable to the sixth shaft TM6.

In addition, each of the seventh shaft TM7, the eighth shaft TM8, andninth shaft TM9 is selectively connectable to the transmission housing Hto be operated as a selective fixed element.

Three clutches C1, C2, and C3 that are engaging elements are disposed atportions at which any two shafts among the nine shafts TM1 to TM9including the input shaft IS and the output shaft OS are selectivelyconnectable to each other.

In addition, three brakes B1, B2, and B3 that are engaging elements aredisposed at portions at which any one shaft among the nine shafts TM1 toTM9 is selectively connectable to the transmission housing H.

Arrangement of the six engaging elements (three clutches C1 to C3 andthree brakes B1 to B3) will be described in detail.

The first clutch C1 is disposed between the second shaft TM2 and thefifth shaft TM5 and selectively connects the second shaft TM2 to thefifth shaft TM5.

The second clutch C2 is disposed between the third shaft TM3 and thesixth shaft TM6 and selectively connects the third shaft TM3 to thesixth shaft TM6.

The third clutch C3 is disposed between the fourth shaft TM4 and thesixth shaft TM6 and selectively connects the fourth shaft TM4 to thesixth shaft TM6.

The first brake B1 is disposed between the seventh shaft TM7 and thetransmission housing H and selectively connects and fixes the seventhshaft TM7 to the transmission housing H.

The second brake B2 is disposed between the eighth shaft TM8 and thetransmission housing H and selectively connects and fixes the eighthshaft TM8 to the transmission housing H.

The third brake B3 is disposed between the ninth shaft TM9 and thetransmission housing H and selectively connects and fixes the ninthshaft TM9 to the transmission housing H.

The engaging elements including the first, second, and third clutchesC1, C2, and C3 and the first, second, and third brakes B1, B2, and B3may be multi-plates friction elements of wet type that are operated byhydraulic pressure. Multi-plates friction elements of wet type aremainly used as the engaging elements, but dog clutches, electricclutches, or magnetic clutches that may be operated by electric signalfrom an electric control device may be used as the engaging elements.

FIG. 2 is an operation chart of engaging elements at each speed stage inthe planetary gear train according to the various exemplary embodimentsof the present invention.

Referring to FIG. 2, any three combinations among the first, second, andthird clutches C1, C2, and C3 and the first, second, and third brakesB1, B2, and B3 are operated to achieve ten forward speeds and onereverse speed. Shifting processes will be described.

The second clutch C2 and the second and third brakes B2 and B3 areoperated at a first forward speed D1.

In a state that the third shaft TM3 is fixedly connected to the sixthshaft TM6 by operation of the second clutch C2, torque of the inputshaft IS is input to the first shaft TM1.

At this state, the eighth and ninth shafts TM8 and TM9 are operated asthe fixed elements by operation of the second and third brakes B2 andB3. Therefore, the torque of the input shaft IS is shifted into thefirst forward speed, and the first forward speed is output through theoutput shaft OS fixedly connected to the second shaft TM2.

The third clutch C3 and the second and third brakes B2 and B3 areoperated at a second forward speed D2.

In a state that the fourth shaft TM4 is fixedly connected to the sixthshaft TM6 by operation of the third clutch C3, the torque of the inputshaft IS is input to the first shaft TM1.

At this state, the eighth and ninth shafts TM8 and TM9 are operated asthe fixed elements by operation of the second and third brakes B2 andB3. Therefore, the torque of the input shaft IS is shifted into thesecond forward speed, and the second forward speed is output through theoutput shaft OS fixedly connected to the second shaft TM2.

The third clutch C3 and the first and third brakes B1 and B3 areoperated at a third forward speed D3.

In a state that the fourth shaft TM4 is fixedly connected to the sixthshaft TM6 by operation of the third clutch C3, the torque of the inputshaft IS is input to the first shaft TM1.

At this state, the seventh and ninth shafts TM7 and TM9 are operated asthe fixed elements by operation of the first and third brakes B1 and B3.Therefore, the torque of the input shaft IS is shifted into the thirdforward speed, and the third forward speed is output through the outputshaft OS fixedly connected to the second shaft TM2.

The second and third clutches C2 and C3 and the third brake B3 areoperated at a fourth forward speed D4.

In a state that the third shaft TM3 is fixedly connected to the sixthshaft TM6 by operation of the second clutch C2 and the fourth shaft TM4is fixedly connected to the sixth shaft TM6 by operation of the thirdclutch C3, the torque of the input shaft IS is input to the first shaftTM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the fourth forward speed, and the fourthforward speed is output through the output shaft OS fixedly connected tothe second shaft TM2.

The first and third clutches C1 and C3 and the third brake B3 areoperated at a fifth forward speed D5.

In a state that the second shaft TM2 is fixedly connected to the fifthshaft TM5 by operation of the first clutch C1 and the fourth shaft TM4is fixedly connected to the sixth shaft TM6 by operation of the thirdclutch C3, the torque of the input shaft IS is input to the first shaftTM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the fifth forward speed, and the fifth forwardspeed is output through the output shaft OS fixedly connected to thesecond shaft TM2.

The first clutch and second clutch C1 and C2 and the third brake B3 areoperated at a sixth forward speed D6.

In a state that the second shaft TM2 is fixedly connected to the fifthshaft TM5 by operation of the first clutch C1 and the third shaft TM3 isfixedly connected to the sixth shaft TM6 by operation of the secondclutch C2, the torque of the input shaft IS is input to the first shaftTM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the sixth forward speed, and the sixth forwardspeed is output through the output shaft OS fixedly connected to thesecond shaft TM2.

The first, second, and third clutches C1, C2, and C3 are operated at aseventh forward speed D7.

Therefore, the second shaft TM2 is fixedly connected to the fifth shaftTM5 by operation of the first clutch C1, the third shaft TM3 is fixedlyconnected to the sixth shaft TM6 by operation of the second clutch C2,and the fourth shaft TM4 is fixedly connected to the sixth shaft TM6 byoperation of the third clutch C3.

In the instant case, the first, second, third, fourth, and fifthplanetary gear sets PG1, PG2, PG3, PG4, and PG5 become lock-up states.Therefore, the torque of the input shaft IS input to the first shaft TM1is output through the output shaft OS fixedly connected to the secondshaft TM2 without rotation speed change.

The first clutch and second clutch C1 and C2 and the second brake B2 areoperated at an eighth forward speed D8.

In a state that the second shaft TM2 is fixedly connected to the fifthshaft TM5 by operation of the first clutch C1 and the third shaft TM3 isfixedly connected to the sixth shaft TM6 by operation of the secondclutch C2, the torque of the input shaft IS is input to the first shaftTM1.

At this state, the eighth shaft TM8 is operated as the fixed element byoperation of the second brake B2. Therefore, the torque of the inputshaft IS is shifted into the eighth forward speed, and the eighthforward speed is output through the output shaft OS fixedly connected tothe second shaft TM2.

The first clutch C1 and the first and second brakes B1 and B2 areoperated at a ninth forward speed D9.

In a state that the second shaft TM2 is fixedly connected to the fifthshaft TM5 by operation of the first clutch C1, the torque of the inputshaft IS is input to the first shaft TM1.

At this state, the seventh and eighth shafts TM7 and TM8 are operated asthe fixed elements by operation of the first and second brakes B1 andB2. Therefore, the torque of the input shaft IS is shifted into theninth forward speed, and the ninth forward speed is output through theoutput shaft OS fixedly connected to the second shaft TM2.

The first and third clutches C1 and C3 and the second brake B2 areoperated at a tenth forward speed D10.

In a state that the second shaft TM2 is fixedly connected to the fifthshaft TM5 by operation of the first clutch C1 and the fourth shaft TM4is fixedly connected to the sixth shaft TM6 by operation of the thirdclutch C3, the torque of the input shaft IS is input to the first shaftTM1.

At this state, the eighth shaft TM8 is operated as the fixed element byoperation of the second brake B2. Therefore, the torque of the inputshaft IS is shifted into the tenth forward speed, and the tenth forwardspeed is output through the output shaft OS fixedly connected to thesecond shaft TM2.

The second clutch C2 and the first and third brakes B1 and B3 areoperated at a reverse speed REV.

In a state that the third shaft TM3 is fixedly connected to the sixthshaft TM6 by operation of the second clutch C2, the torque of the inputshaft IS is input to the first shaft TM1.

At this state, the seventh and ninth shafts TM7 and TM9 are operated asthe fixed elements by operation of the first and third brakes B1 and B3.Therefore, the torque of the input shaft IS is shifted into the reversespeed, and the reverse speed is output through the output shaft OSfixedly connected to the second shaft TM2.

FIG. 3 is a schematic diagram of a planetary gear train according tovarious exemplary embodiments of the present invention.

Layout and operation of the planetary gear train according to thevarious exemplary embodiments of the present invention is similar tothose of the planetary gear train according to the various exemplaryembodiments of the present invention. Therefore, differences between thevarious exemplary embodiments and the various exemplary embodiments willbe described.

Referring to FIG. 1 and FIG. 3, the planetary gear sets are disposed ina sequence of the first, third, second, fourth, and fifth planetary gearsets PG1, PG3, PG2, PG4, and PG5 from the engine side on an axis of theinput shaft IS in the planetary gear train in the various exemplaryembodiments of the present invention, but the planetary gear sets aredisposed in a sequence of the first, second, third, fourth, and fifthplanetary gear sets PG1, PG2, PG3, PG4, and PG5 from the engine side onan axis of the input shaft IS in the planetary gear train according tothe various exemplary embodiments of the present invention.

According to the exemplary embodiments of the present invention, tenforward speeds and one reverse speed may be achieved by use of fiveplanetary gear sets PG1, PG2, PG3, PG4, and PG5 and six engagingelements including three clutches C1, C2, and C3 and three brakes B1,B2, and B3.

In addition, since gear ratio span greater than 8.4 is secured, drivingefficiency of the engine may be maximized. In addition, since linearityof step ratios may be secured due to multiple speed stages, drivabilityincluding acceleration before and after shift, rhythmical engine speed,and the like may be improved.

In addition, since ten forward speeds and one reverse speeds areachieved by use of the minimized number of engaging elements, drag lossof clutches and brakes may be reduced and power delivery efficiency andfuel economy may be improved.

In addition, since torque parallel way is applied to a planetary gearset at an output side and torque is evenly shared to each planetary gearset and each engaging element, torque delivery efficiency and durabilitymay be improved.

In addition, since five planetary gear sets are used to achieve tenforward speeds and one reverse speed, flexibility of output gear ratiosmay be increased and linearity of step ratios may be improved.

For convenience in explanation and accurate definition in the appendedclaims, the terms “upper”, “lower”, “internal”, “outer”, “up”, “down”,“upper”, “lower”, “upwards”, “downwards”, “front”, “rear”, “back”,“inside”, “outside”, “inwardly”, “outwardly”, “internal”, “external”,“internal”, “outer”, “forwards”, and “backwards” are used to describefeatures of the exemplary embodiments with reference to the positions ofsuch features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described toexplain certain principles of the invention and their practicalapplication, to enable others skilled in the art to make and utilizevarious exemplary embodiments of the present invention, as well asvarious alternatives and modifications thereof. It is intended that thescope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. A planetary gear train apparatus of an automatictransmission for a vehicle, the planetary gear train apparatuscomprising: an input shaft receiving torque of an engine; an outputshaft outputting torque; a first planetary gear set including a firstrotation element, a second rotation element, and a third rotationelement; a second planetary gear set including a fourth rotationelement, a fifth rotation element, and a sixth rotation element; a thirdplanetary gear set including a seventh rotation element, an eighthrotation element, and a ninth rotation element; a fourth planetary gearset including a tenth rotation element, an eleventh rotation element,and a twelfth rotation element; a fifth planetary gear set including athirteenth rotation element, a fourteenth rotation element, and afifteenth rotation element; a first shaft fixedly connected to the firstrotation element and the sixth rotation element and fixedly connected tothe input shaft; a second shaft fixedly connected to the fourteenthrotation element and the output shaft; a third shaft fixedly connectedto the third rotation element and the seventh rotation element; a fourthshaft fixedly connected to the fifth rotation element and the eighthrotation element; a fifth shaft fixedly connected to the ninth rotationelement and the tenth rotation element; a sixth shaft fixedly connectedto the eleventh rotation element and the fifteenth rotation element; anda plurality of shafts formed by combinations of remaining rotationelements among the first to fifteenth rotation elements that are notconnected to the first to sixth shafts, and each thereof selectivelyconnectable to a transmission housing.
 2. The planetary gear trainapparatus of claim 1, wherein the plurality of shafts comprise: aseventh shaft fixedly connected to the second rotation element and thefourth rotation element and selectively connectable to the transmissionhousing; an eighth shaft fixedly connected to the twelfth rotationelement and selectively connectable to the transmission housing; and aninth shaft fixedly connected to the thirteenth rotation element andselectively connectable to the transmission housing, and wherein thesecond shaft is selectively connectable to the fifth shaft, the thirdshaft is selectively connectable to the sixth shaft, and the fourthshaft is selectively connectable to the sixth shaft.
 3. The planetarygear train apparatus of claim 2, further comprising: three clutches,each selectively connecting one shaft to another shaft among the secondto sixth shafts; and three brakes, each selectively connecting one ofthe seventh shaft, the eighth shaft, and the ninth shaft to thetransmission housing.
 4. The planetary gear train apparatus of claim 3,wherein the three clutches comprise: a first clutch mounted between thesecond shaft and the fifth shaft; a second clutch mounted between thethird shaft and the sixth shaft; and a third clutch mounted between thefourth shaft and the sixth shaft, and wherein the three brakes includes:a first brake mounted between the seventh shaft and the transmissionhousing; a second brake mounted between the eighth shaft and thetransmission housing; and a third brake mounted between the ninth shaftand the transmission housing.
 5. The planetary gear train apparatus ofclaim 1, wherein the first rotation element is a first sun gear, thesecond rotation element is a first planet carrier, and the thirdrotation element is a first ring gear, the fourth rotation element is asecond sun gear, the fifth rotation element is a second planet carrier,and the sixth rotation element is a second ring gear, the seventhrotation element is a third sun gear, the eighth rotation element is athird planet carrier, and the ninth rotation element is a third ringgear, the tenth rotation element is a fourth sun gear, the eleventhrotation element is a fourth planet carrier, and the twelfth rotationelement is a fourth ring gear, and the thirteenth rotation element is afifth sun gear, the fourteenth rotation element is a fifth planetcarrier, and the fifteenth rotation element is a fifth ring gear.
 6. Theplanetary gear train apparatus of claim 1, wherein the first, second,third, fourth, and fifth planetary gear sets are disposed in a sequenceof the first, third, second, fourth, and fifth planetary gear sets froman engine side on an axis of the input shaft.
 7. The planetary geartrain apparatus of claim 1, wherein the first, second, third, fourth,and fifth planetary gear sets are disposed in a sequence of the first,second, third, fourth, and fifth planetary gear sets from an engine sideon an axis of the input shaft.
 8. A planetary gear train apparatus of anautomatic transmission for a vehicle, the planetary gear train apparatuscomprising: an input shaft receiving torque of an engine; an outputshaft outputting torque; a first planetary gear set including a firstrotation element, a second rotation element, and a third rotationelement; a second planetary gear set including a fourth rotationelement, a fifth rotation element, and a sixth rotation element; a thirdplanetary gear set including a seventh rotation element, an eighthrotation element, and a ninth rotation element; a fourth planetary gearset including a tenth rotation element, an eleventh rotation element,and a twelfth rotation element; and a fifth planetary gear set includinga thirteenth rotation element, a fourteenth rotation element, and afifteenth rotation element, wherein the first rotation element isfixedly connected to the input shaft, the fourteenth rotation element isfixedly connected to the output shaft, the first rotation element isfixedly connected to the sixth rotation element, the second rotationelement is fixedly connected to the fourth rotation element andselectively connectable to a transmission housing, the third rotationelement is fixedly connected to the seventh rotation element, the fifthrotation element is fixedly connected to the eighth rotation element,the ninth rotation element is fixedly connected to the tenth rotationelement and selectively connectable to the fourteenth rotation element,the eleventh rotation element is fixedly connected to the fifteenthrotation element and selectively connectable to the third rotationelement and the eighth rotation element, the twelfth rotation element isselectively connectable to the transmission housing, and the thirteenthrotation element is selectively connectable to the transmission housing.9. The planetary gear train apparatus of claim 8, further comprising:three clutches, each selectively connecting one rotation element toanother rotation element among the first to fifteenth rotation elements;and three brakes, each selectively connecting one of the second rotationelement, the twelve rotation element, and the thirteenth rotationelement to the transmission housing.
 10. The planetary gear trainapparatus of claim 9, wherein the three clutches comprise: a firstclutch mounted between the tenth rotation element and the fourteenthrotation element; a second clutch mounted between the third rotationelement and the eleventh rotation element; and a third clutch mountedbetween the eighth rotation element and the eleventh rotation element,and wherein the three brakes comprise: a first brake mounted between thesecond rotation element and the transmission housing; a second brakemounted between the twelfth rotation element and the transmissionhousing; and a third brake mounted between the thirteenth rotationelement and the transmission housing.
 11. The planetary gear trainapparatus of claim 8, wherein the first rotation element is a first sungear, the second rotation element is a first planet carrier, and thethird rotation element is a first ring gear, the fourth rotation elementis a second sun gear, the fifth rotation element is a second planetcarrier, and the sixth rotation element is a second ring gear, theseventh rotation element is a third sun gear, the eighth rotationelement is a third planet carrier, and the ninth rotation element is athird ring gear, the tenth rotation element is a fourth sun gear, theeleventh rotation element is a fourth planet carrier, and the twelfthrotation element is a fourth ring gear, and the thirteenth rotationelement is a fifth sun gear, the fourteenth rotation element is a fifthplanet carrier, and the fifteenth rotation element is a fifth ring gear.12. The planetary gear train apparatus of claim 8, wherein the first,second, third, fourth, and fifth planetary gear sets are disposed in asequence of the first, third, second, fourth, and fifth planetary gearsets from an engine side on an axis of the input shaft.
 13. Theplanetary gear train apparatus of claim 8, wherein the first, second,third, fourth, and fifth planetary gear sets are disposed in a sequenceof the first, second, third, fourth, and fifth planetary gear sets froman engine side on an axis of the input shaft.